A fluid motaion
enabled by physics

Free Swing

A pendulum is a weight suspended from a pivot so that it can swing freely. When a pendulum is displacaed sideways from its resting, equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the equilibrium position.


When out of phase pendulums are properly constructed, cool wave motion results. The real trick lies in setting the appropriate lengths and then starting them all at the same time and angle. The equations of motion are fairly simple, d2dt2+glsin = 0 repeated for each length. The lengths are determined by 16 T1=(16+(n-1) )Tn.


In physics and mathematics, in the area of dynamical systems, a double pendulum is a pendulum with another pendulum attached to its end, and is a simple physical system that exhibits rich dynamic behavior with a strong sensitivity to initial conditions. The motion of a double pendulum is governed by a set of coupled ordinary differential equations and is chaotic.

Sine waves

A pendulum is essentially just a sine wave that loses its amplitude (peak) over time. Music works with these kind of waves (along with others) to create intricate sounds (what defines the sound of a guitar or a piano) by combining sinewaves of different frequencies.


While playing a single sinewave you will hear a flat note. Playing two inverted sine waves leads to silence; since you sum opposing amplitudes.
However if you mix sinewaves of similiar frequencies you can make the interfering waves audible (called "beat").

 Click the buttons
to see the sine waves and hear what happens when you mix similiar frequencies.